cooling fan
#1
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cooling fan
I'm in the process of restoring the engine bay in my 79 vette. the car has the L82 engine option. when i removed the clutch cooling fan i noticed it only had 5 blades instead of 7 blades, this does not seem correct to me .It also has the electric fan mounted up against the rad ,also on the fan shroud on the bottom it is cut like there is a baffle that moves back and forth.I just bought this car in the fall, so far everything has been close to origional. It seems to be set up different than the 77 that i restored 2 years ago. The 5 blade fan is what really is confusing me . Any answers would really help. Thanks.
#2
Drifting
hegazman
I have a 79 L-82 with the mechanical and electric fan. The mechanical was only five blades. I have since converted to a dual electric fan. But, a five blade fan is original on this model.
#3
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Yep, 5 blades on the 79 L82. I BELIEVE it was an attempt to quiet it down some.
The electric auxiliary fan doesn't turn on until temp hits 238 or so. It's possible you'll never even see it run.
The shroud with the flapper in the bottom with the electric fan is exclusive to 79 and 80 L82s with air.
The electric auxiliary fan doesn't turn on until temp hits 238 or so. It's possible you'll never even see it run.
The shroud with the flapper in the bottom with the electric fan is exclusive to 79 and 80 L82s with air.
Last edited by KapsSA; 01-14-2009 at 08:00 PM.
#4
Team Owner
I not saying I"m a expert on any GM car of these generations, but AFAIK, the only cars coming with 7 blade viscous fans were Caddys.....
and I have seen with 7 bladed stainless flex fans too....
and I have seen with 7 bladed stainless flex fans too....
#6
Melting Slicks
The vette books say the 5 blade fan is used because it robs less horsepower! The 80 L82 I am working on has 5 blades and the electric one also. It would be nice to make the electric fan come on at a lower temp??
Recommend that you make sure the thermo clutch is working and you should be OK.
Recommend that you make sure the thermo clutch is working and you should be OK.
#8
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It wasn't an emissions thing, it was because of noise restrictions.
Chicago/Cook Co. was one of these cities.
I bought my black79 back in 1984 from the "second" owner. I used the quotes because this guy had his brother purchase the Vette for him to skirt the restrictions. A year later he transferred the title to his name as a used car.
I imagine the hp increase was more of a side benefit. The 79 L82 was only 5hp more than the 78 L82, mostly because of the less restrictive mufflers.
Last edited by KapsSA; 01-14-2009 at 11:13 PM.
#9
I have a 79 L82 too and that auxiliary fan.
I made a mod on that. I bypassed the aux fan switch on the engine and take out 2 wires from the aux fan fuse holder under the dash . then took those 2 wires to a 30A switch inside the cockpit. In this way I can start that aux fan when i want . and it has been helpful in hot summer time. the engine cools down in few secs
I made a mod on that. I bypassed the aux fan switch on the engine and take out 2 wires from the aux fan fuse holder under the dash . then took those 2 wires to a 30A switch inside the cockpit. In this way I can start that aux fan when i want . and it has been helpful in hot summer time. the engine cools down in few secs
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Thanks everyone, it seems that i have the correct one.I just have to find a replacement fanclutch,also i think i will replace the temp sender so the aux fan comes on sooner.
#11
Drifting
thegazman
You can buy a engine temperature sensor that will turn you electric fan on at lower temperatures. If you're running a 180 degree thermostat. you can get a sensor that will turn the fan on at 185.
#12
Which means it will run continuously. There is no reason to attempt to overcool an SBC. They are happy to run non-stop at 195-200+ and beyond. Just like GM designed them to do.
The thermostat set temperature is the MINIMUM acceptable running temp, not the maximum.
#13
Drifting
thegazman
You are absolutely right!!! I was just saying you can buy a temperature sensor with a lower setting. However, I personally don't want my car running at 220 to 235 before the extra aux. fan comes on.
#14
Melting Slicks
i used this kit for my aux. fan, on my 79 L82, 200*on 185*off , it works fine, usually comes on when i run the AC.
http://www.jegs.com/i/JEGS/555/10561/10002/-1
http://www.jegs.com/i/JEGS/555/10561/10002/-1